Obviously the best solution in your case IS to add another hard drive but I'll give you a few more suggestions for freeing up space anyway, as it may help others with similar problems....
BTW - I have a relatively fresh installation of XP Pro SP2 on my laptop at the moment, with Office 2003, Firefox, Outpost Pro and several other programs installed, and it takes up a fraction over 3GB in total including the swap file... Admittedly, I don't use any email clients on my laptop which probably helps.
* Delete the temporary internet cache & cookies (including offline files)
* Delete the contents of the temp folder .In XP, this is located in Documents & settings\%user_profile%\local settings\temp. NB The local settings folder is hidden so you'll need to have hidden & system files visible (See 'My computer -> Tools -> Folder Options ->View' tab)
* Uninstall any Office applications that you don't use.
* If you use an email client (as opposed to web mail), then go through your email mail boxes & delete the contents of the Trash/Junk folders, go through the email in your inbox & sent box and delete any email you don't need to keep. Then empty the Deleted email folder.
* Delete all old restore points. This method allows you to keep the most recent ones however.
Go to Start->Run and type cleanmgr.exe (click OK). Select a hard drive letter (usually C) & wait for disk cleanup to calculate the amount of space that can be freed up, then click on the More Options tab & click the 'Clean up' button under System Restore.
* If you have a lot of stuff in My Documents etc, especially big stuff like music, photos or video files, consider transferring them to CD/DVD etc instead of storing them on the computer. Do not rely on floppy disks or flash sticks as your sole form of storage though for anything important.
* Finially, empty the recycle bin & defragment the drive again
Edited by Samm, 24 September 2008 - 04:41 PM.